It's a song; it's a book; it's the cliche of the year. George Bush and Bill Clinton did it; John Major tried to do it; Tony Blair has done it twice; Gordon Brown is still doing it. And it's nowhere to be found in the Oxford English Dictionary. This year, however, there has been a verbal epidemic in usage of the expression "hit the ground running", as the following table shows:

The table indicates the total number of occurrences of the phrase "hit the ground running" for each of the past four years, and for each month so far this year, in our database of a representative cross-section of national newspapers. As can be seen, the expression grew gradually in usage in the mid-Nineties, slipped back in 1996, but after ominous rumblings during the election campaign suddenly erupted as "hit the ground running" became the catch phrase of Tony Blair's new government.

The history of the phrase is obscure. Brewer's Twentieth Century Phrase and Fable says that it "probably derives from ... activities such as parachuting and being able to run off immediately one touches the ground ... and from the rapid disembarking of troops from helicopters (as practised in the Vietnam War)". Yet hitting the ground running could have been equally advantageous in earlier wars. However, neither at the time of Vietnam, nor in connection with the D-Day landings, have we been able to find an example of the phrase.

The first ground-hitting running politician of whom we have any record is George Bush, who did it in Time magazine, in an article even entitled "Hitting the Ground Running" which appeared two weeks after he took office in 1989. Three years later, in the issue of 3 February 1992, Boutros Boutros- Ghali also hit the ground running when he became Secretary-General of the United Nations, and in the following year, the business guru and sports impresario Mark McCormack published a book of tips for dealing with travel and hotels, entitled Hitting the Ground Running. Also in 1993, the New Zealand singer Tim Finn reached number 50 in the British charts with "Hit the Ground Running".

Interestingly, our database reveals no occurrences of the phrases "hit the ground jogging" or "hit the ground limping", but there have been four sightings in the past few weeks of "hit the ground sprinting". It is even more interesting, however, to trace the aetiology of the current HTGR boom.

Although Tony Blair had "been determined to hit the ground running" as soon as he became the Labour leader, it was John Major who was determined, according to "senior ministers" quoted on 17 March, to "hit the ground running" at the start the recent election campaign. On 23 March, however, a "Tory aide" was quoted as groaning: "We said we would hit the ground running. Instead we just hit the ground."

And dropped the baton for Tony Blair and Gordon Brown to pick up, apparently, for they were the ones who cornered the market in HTGR for the rest of the campaign - apart from a single incident on 6 April, when "a young LibDem minder" was quoted as saying of Paddy Ashdown: "He's hit the ground running."

What of other favourite cliches? Apart from HTGR, this has also been a splendid year for defining moments. The table below charts the numbers of defining moments in the pages of The Independent and the Independent on Sunday in recent years.

We had thought that 1995 had seen defining moments peaking, yet 1997 looks set to beat it. Another one to look out for is the "third way" of which Mr Blair is so fond. Our database has averaged one "third way" every 1.35 days since Labour took power, compared with one per 2.1 days in the two preceding years. Clearly a cliche that has hit the ground running.

Ground running hits: 1993-97

1993 21

1994 36

1995 49

1996 42

1997: Jan 3

Feb 6

Mar 12

Apr 13

May 63

Jun (1-22) 16

1997 total to date 113

Defining moments: 1993-97

1994 27

1995 75

1996 46

1997 (to date) 41